In a semiconductor manufacturing apparatus used for performing a dry process, plasma coating, or the like in production of a semiconductor, a highly reactive F or Cl based plasma is used for etching or cleaning. Therefore, a member used for such an apparatus necessarily has high corrosion resistance, and a member, e.g., an electrostatic chuck or a heater, which comes into contact with a Si wafer is required to have still higher corrosion resistance. Patent Document 1 discloses Yb2O3 and Dy2O3 thin films formed by a PVD method as corrosion-resistant members capable of responding to such a demand. The etching rates of these thin films are very small as compared with the etching rates of an alumina sintered body and the like.